This invention relates to conveyor apparatus comprising a plurality of carrier units that are supported on a rail which guides them for movement, and a driven endless chain having a straight stretch which is parallel and adjacent to a straight section of the rail and to which each carrier unit is drivingly coupled as it moves along that section of the rail.
In a known conveyor apparatus of this type, as described in DE-PS No. 2,344,533, an inclined conveying stretch is provided with a driven endless roller chain having a working portion extending below the conveyor rail, and a return portion guided at a certain distance above the conveyor rail, the latter being formed with a guide edge for the working portion of the chain. Each carrier unit is provided with a coupling member in the form of a resilient crossbar extending tranversely of the travelling direction. Adjacent the inclined conveyor stretch the crossbar contacts the roller chain and comes into clamping engagement with a chain link. This engagement is brought about by proper selection of the spacings between the crossbar and the carrier rollers on the one hand, and between the conveyor rail and the working portion of the chain on the other. In order to achieve reliable engagement, the upper side of the known crossbar is cambered to conform to the shape of the roller chain link.
Even so, however, the engagement between the clamping elements and the roller chain amounts to no more than about 1.5 mm. It has been found that in the course of time the chain guide edge of the conveyor rail is flattened down, resulting in a considerable play between the clamping elements and the chain, so that, particularly when rather heavy goods are to be conveyed, the engagement depth between the chain and the coupling elements is no longer sufficient to ensure reliable conveyance.